In a technical field of chemical reactions, a chemical reactor has been known wherein a fluid material flows in a flow path formed in a substrate so as to produce a desired fluid material by a chemical reaction. Some of such conventional chemical reactors are small in size and have a flow path on a micron or millimeter scale which is formed in a small-sized substrate by use of a micro fabrication technique accumulated by a semiconductor manufacturing technique for semiconductor integrated circuits or the like, and PCT National Publication No. 2001-524019 shows a chemical micro reactor with a plurality of laminated substrates in which paths for a reacting fluid are formed. Such chemical reactors promote a reaction by heating a reaction furnace, and the reaction furnace itself is small, thus offering advantages that uniform heat can be transmitted and a reaction can be uniformly induced.
In one chemical reactor which causes a plurality of reactions, suitable temperature for each reaction may differ, so that the temperature needs to be changed locally.
Therefore, according to advantages of this invention, a chemical reactor and a fuel cell system are provided which are capable of performing a plurality of chemical reactions and allow the entire reactor to be simplified and small in size.